The tornado touched down around 1:15 p.m., according to video footage reviewed by weather officials, during a Tornado Warning that had been issued for the county and expired at 1:45 p.m. The storm caused minor damage to the ChristianaCare campus in Newark, Delaware, including to a helicopter and helipads, a hospital spokesperson said.

“In this afternoon’s storm, Newark Campus appears to have been impacted by a tornado or high winds, which have caused some minor damage to property,” the spokesperson said. “Our Facilities, Public Safety and Emergency Management team are assessing the situation. We are assessing damage to our helicopter and helipads, otherwise there does not appear to be any impact to operations. We continue to provide care and services without interruption.”

The severe weather prompted a First Alert across the entire Philadelphia region from 11 a.m. to 7 p.m. A Tornado Watch remained in effect for the region, including parts of South Jersey and Delaware, until 7 p.m. A separate Tornado Warning was issued for Burlington County, New Jersey, around 3:45 p.m. and was set to expire at 4:15 p.m.

A Flash Flood Warning was also issued for Burlington County in New Jersey, as well as Philadelphia, Montgomery, and Bucks counties in Pennsylvania, until 7:30 p.m., according to the National Weather Service.

Earlier in the afternoon, a Severe Thunderstorm Warning was in effect for southeastern Berks County and north central Chester County until 1:30 p.m.

The storm system also disrupted transportation. A large cargo ship crashed into the Tacony-Palmyra Bridge on Thursday, leaving the bridge unable to close, according to Pennsylvania State Rep. Ed Neilson. Traffic between Pennsylvania and New Jersey was disrupted, and officials urged drivers to find alternate routes. Heavier congestion was expected on other bridges crossing the Delaware River.

Forecasters said the thunderstorm threat would diminish into the evening, but rain remained likely Thursday night and wet weather was expected to continue into Friday evening. Thursday’s high in Philadelphia was 61 degrees.

A wind shift Thursday night was expected to usher colder air into the region, with temperatures dropping into the 40s and winds gusting up to 35 mph. Friday temperatures were expected to feel like the 30s.

The weekend was forecast to be dry but gusty, with a high of 48 degrees on Saturday and wind chills in the low 40s. Sunday was expected to be breezy with seasonable temperatures in the low 50s.

The National Weather Service advises residents to review emergency plans and identify a safe room in case of future warnings. “Acting early helps to save lives,” the agency states.